MirageSector

MirageSector — Object representing a sector.

Synopsis

#include <mirage-sector.h>

                    MirageSector;
struct              MirageSectorClass;
enum                MirageSectorSubchannelFormat;
enum                MirageSectorValidData;
gboolean            mirage_sector_feed_data             (MirageSector *self,
                                                         gint address,
                                                         MirageTrack *track,
                                                         GError **error);
gboolean            mirage_sector_get_data              (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
gboolean            mirage_sector_get_edc_ecc           (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
gboolean            mirage_sector_get_header            (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
MirageTrackModes    mirage_sector_get_sector_type       (MirageSector *self);
gboolean            mirage_sector_get_subchannel        (MirageSector *self,
                                                         MirageSectorSubchannelFormat format,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
gboolean            mirage_sector_get_subheader         (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
gboolean            mirage_sector_get_sync              (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);
gboolean            mirage_sector_verify_lec            (MirageSector *self);
gboolean            mirage_sector_verify_subchannel_crc (MirageSector *self);

Object Hierarchy

  GObject
   +----MirageObject
         +----MirageSector

Implemented Interfaces

MirageSector implements MirageContextual.

Description

MirageSector object represents a sector. It provides access to the sector data, generating it if needed.

Details

MirageSector

typedef struct _MirageSector MirageSector;

All the fields in the MirageSector structure are private to the MirageSector implementation and should never be accessed directly.


struct MirageSectorClass

struct MirageSectorClass {
    MirageObjectClass parent_class;
};

The class structure for the MirageSector type.

MirageObjectClass parent_class;

the parent class

enum MirageSectorSubchannelFormat

typedef enum {
    MIRAGE_SUBCHANNEL_PW = 0x01,
    MIRAGE_SUBCHANNEL_PQ = 0x02,
    MIRAGE_SUBCHANNEL_RW = 0x03
} MirageSectorSubchannelFormat;

Subchannel selection flags.

MIRAGE_SUBCHANNEL_PW

PW subchannel; 96 bytes, interleaved P-W

MIRAGE_SUBCHANNEL_PQ

PQ subchannel; 16 bytes, Q subchannel

MIRAGE_SUBCHANNEL_RW

RW subchannel; 96 bytes, deinterleaved R-W

enum MirageSectorValidData

typedef enum {
    MIRAGE_VALID_SYNC      = 0x01,
    MIRAGE_VALID_HEADER    = 0x02,
    MIRAGE_VALID_SUBHEADER = 0x04,
    MIRAGE_VALID_DATA      = 0x08,
    MIRAGE_VALID_EDC_ECC   = 0x10,
    MIRAGE_VALID_SUBCHAN   = 0x20,
} MirageSectorValidData;

Sector data validity flags.

MIRAGE_VALID_SYNC

sync pattern valid

MIRAGE_VALID_HEADER

header valid

MIRAGE_VALID_SUBHEADER

subheader valid

MIRAGE_VALID_DATA

user data valid

MIRAGE_VALID_EDC_ECC

EDC/ECC data valid

MIRAGE_VALID_SUBCHAN

subchannel valid

mirage_sector_feed_data ()

gboolean            mirage_sector_feed_data             (MirageSector *self,
                                                         gint address,
                                                         MirageTrack *track,
                                                         GError **error);

Feeds data to sector. It finds appropriate fragment to feed from, reads data into sector object and sets data validity flags.

Note

Intended for internal use.

self :

a MirageSector

address :

address the sector represents. Given in sectors. [in]

track :

track the sector belongs to. [in]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_data ()

gboolean            mirage_sector_get_data              (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's user data. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

self :

a MirageSector

ret_buf :

location to store pointer to buffer containing user data, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of user data, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_edc_ecc ()

gboolean            mirage_sector_get_edc_ecc           (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's EDC/ECC data. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

If EDC/ECC data is not provided by image file(s), it is generated.

self :

a MirageSector

ret_buf :

location to store pointer to buffer containing EDC/ECC data, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of EDC/ECC data, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_header ()

gboolean            mirage_sector_get_header            (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's header. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

If header is not provided by image file(s), it is generated.

self :

a MirageSector

ret_buf :

location to store pointer to buffer containing header, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of header, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_sector_type ()

MirageTrackModes    mirage_sector_get_sector_type       (MirageSector *self);

Retrieves sector type (track mode); one of MirageTrackModes.

self :

a MirageSector

Returns :

sector type (track mode)

mirage_sector_get_subchannel ()

gboolean            mirage_sector_get_subchannel        (MirageSector *self,
                                                         MirageSectorSubchannelFormat format,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's subchannel. format must be one of MirageSectorSubchannelFormat. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

If subchannel is not provided by image file(s), it is generated.

self :

a MirageSector

format :

subchannel format. [in]

ret_buf :

location to store pointer to buffer containing subchannel, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of subchannel data, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_subheader ()

gboolean            mirage_sector_get_subheader         (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's subheader. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

If subheader is not provided by image file(s), it is generated.

self :

a MirageSector

ret_buf :

location to store pointer to buffer containing subheader, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of subheader, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_get_sync ()

gboolean            mirage_sector_get_sync              (MirageSector *self,
                                                         const guint8 **ret_buf,
                                                         gint *ret_len,
                                                         GError **error);

Retrieves sector's sync pattern. The pointer to appropriate location in sector's data buffer is stored into ret_buf; therefore, the buffer should not be modified.

If sync pattern is not provided by image file(s), it is generated.

self :

a MirageSector

ret_buf :

location to store pointer to buffer containing sync pattern, or NULL. [out][transfer none][allow-none][array length=ret_len]

ret_len :

location to store length of sync pattern, or NULL. Length is given in bytes. [out][allow-none]

error :

location to store error, or NULL. [out][allow-none]

Returns :

TRUE on success, FALSE on failure

mirage_sector_verify_lec ()

gboolean            mirage_sector_verify_lec            (MirageSector *self);

Verifies the sector data in terms of L-EC error detection/correction. Data sectors (Mode 1, Mode 2 Form 1 and Mode 2 Form 2) contain error detection/error correction codes which is part of so called layered error correction. This function calculates the EDC for sector data and compares it with EDC provided by the image file.

As a result of comparison, the sectors with intentionally faulty EDC (and possibly ECC, though ECC is not verified) can be discovered.

This function requires EDC/ECC data to be provided by the image. If it is not provided, it would be generated by MirageSector on first access via mirage_sector_get_edc_ecc() using the same algorithm as the one used by this function. Therefore, in case of EDC/ECC data missing, the verification automatically succeeds.

self :

a MirageSector

Returns :

TRUE if sector passes verification (i.e. no L-EC errors are detected) otherwise FALSE

mirage_sector_verify_subchannel_crc ()

gboolean            mirage_sector_verify_subchannel_crc (MirageSector *self);

Verifies the Q subchannel's CRC for the sector.

As a result of comparison, the sectors with intentionally faulty Q subchannel can be discovered.

This function requires subchannel data to be provided by the image. If it is not provided, it would be generated by MirageSector on first access via mirage_sector_get_subchannel() using the same algorithm as the one used by this function. Therefore, in case of subchannel data missing, the verification automatically succeeds.

self :

a MirageSector

Returns :

TRUE if sector's Q subchannel CRC passes verification otherwise FALSE

See Also

MirageTrack